To establish communication with a wireless communication unit, a wireless device typically requests authentication and is registered by a communication system. Communications systems can typically support interconnect and push-to-talk communications as well as a variety of data services. Interconnect communications are typically full-duplex communications, such as a two-way telephone call. Push-to-talk communications, also called dispatch communications, are typically half-duplex communications, such as walkie-talkie and one-way radio communications.
When a wireless device registers in a push-to-talk communication system, the wireless device is typically registered with an application node (such as an application server or similar network element) in the same geographic service region. This registration process can introduce delay where wireless devices participate in a group call, because call completion can require communication across potentially geographically dispersed systems to locate and establish communication with each member of the group call.